This invention relates to a method of making annular bodies from rock material blocks, such as marble, granite, and stone blocks.
While on the one hand, there exists a demand for annular bodies of the kind of annular bodies of marble and the like rock materials which are formed with either cylindrical, or conical, or hyperbolic inner and/or outer surfaces, well known on the other hand, is the great difficulty encountered in producing them.
In order to make annular bodies out of a marble block, a hand carving method may be presently followed which requires, however, craftmanship of a high degree and much time.
Also viable is a mechanical method whereby the block center portion is first hollowed out, e.g. by drilling, and then subjected to rough and finish turning cuts, applied both inside and out, optionally by having the tool bit guided around a template.
The latter scheme practically results in frequent breakage of the marble block being processed, especially where the annular body to be produced is a thin one. This also calls for careful processing, and hence, increased time consumption.